C# equivalent to hash_hmac in PHP

Question

using .NET and C# i need to provide an integrity string using HMAC SHA512 to a PHP server . Using in C# :

Encoding encoding = Encoding.UTF8; byte[] keyByte = encoding.GetBytes(key); HMACSHA512 hmacsha512 = new HMACSHA512(keyByte); byte[] messageBytes = encoding.GetBytes(message); byte[]  hashmessage = hmacsha512.ComputeHash(messageBytes); return(ByteToString(hashmessage).toUpper()); 

But it doesn't match with PHP hash_hmac() PHP code :

$hmac = strtoupper(hash_hmac($pbx_hash, $msg, $binKey)); 

I try to change encoding in C# (utf8, ASCII,Unicode) Without success.

I've tried many solution found on the net but nothing give the same string :(

I can't change the PHP code, and doesn't see what's wrong in C#

Edit This is ByteToString (copied from the comment):

static string ByteToString(byte[] buff) {     string sbinary = "";     for (int i = 0; i < buff.Length; i++)     {         sbinary += buff[i].ToString("X2"); /* hex format */     }     return (sbinary); }     

After many tets, in found that i get the same results if PHP hash_hmac key is a string, not a byte Array . Seems that the problem is with the PHP convert function $binKey = pack("H*", $keyTest);

Answer 1

The problem must be the actual representation of the key/message data.

See the following tests:

PHP

#!/usr/bin/php <?php print strtoupper(hash_hmac("sha256", "message", "key")); ?> 

Output (live via http://writecodeonline.com/php/):

6E9EF29B75FFFC5B7ABAE527D58FDADB2FE42E7219011976917343065F58ED4A 

C#

using System; using System.Text; using System.Security.Cryptography;  public class Program {     private const string key = "key";     private const string message = "message";     private static readonly Encoding encoding = Encoding.UTF8;       static void Main(string[] args)     {         var keyByte = encoding.GetBytes(key);         using (var hmacsha256 = new HMACSHA256(keyByte))         {             hmacsha256.ComputeHash(encoding.GetBytes(message));              Console.WriteLine("Result: {0}", ByteToString(hmacsha256.Hash));         }     }     static string ByteToString(byte[] buff)     {         string sbinary = "";         for (int i = 0; i < buff.Length; i++)             sbinary += buff[i].ToString("X2"); /* hex format */         return sbinary;     }     } 

Output (live via http://ideone.com/JdpeL):

Result: 6E9EF29B75FFFC5B7ABAE527D58FDADB2FE42E7219011976917343065F58ED4A 

So, check the character set/encoding of the PHP input data. Also check the actual algorithm (in $pbx_hash).